It was mostly a lineup of concert music penned by film composers, along with a terrific contemporary tone poem by a hip, 32-year-old comer from the Bay Area, Mason Bates.

Thursday was supposed to have been Leonard Slatkin’s night, for this enterprising conductor offered the West Coast, Left Coast festival perhaps the most adventurous program he has ever concocted for the Los Angeles Philharmonic. It was mostly a lineup of concert music penned by film composers, along with a terrific contemporary tone poem by a hip, 32-year-old comer from the Bay Area, Mason Bates.

Alas, Slatkin suffered a heart attack while conducting in the Netherlands a month ago. He cancelled the rest of his November concerts, but held out on the L.A. ones until last Monday, when his doctors recommended three more weeks of treatments. What to do? On short notice, John Adams, the festival’s already hard-working spark plug, took over two of Slatkin’s pieces and the other two were dealt to the young conductor Jayce Ogren, who fortuitously happens to be a West Coast native himself (from Hoquiam, WA). They saved the show – and it was worth saving.

The lanky, long-limbed Ogren opened by vigorously beating time for Jerry Goldsmith’s Music For Orchestra (recorded by Goldsmith on Telarc), written during a break on his work for “Patton” but bearing no resemblance at all to that film score. This is all-angst-all-the-time, exuberantly orchestrated — Schoenbergian expressionism that packs a compact wallop.

Adams then took the baton for Bates’ “Liquid Interface,” which parlayed the power of water – cracking glaciers, Hurricane Katrina, Berlin’s all-purpose Lake Wannsee – into a spectacular, beautifully organized piece for orchestra and electronica. Bates took a leaf from the early days of wild, pitchless electronic music and propelled it into this century, playing funky electronic patterns himself from a console onstage. The piece reaches its dramatic peak in “Crescent City,” where swinging orchestral jazz is drenched by the storm and the jazz band then seems to float out to sea. #

Ogren returned for Franz Waxman’s “Tristan und Isolde Fantasie,” essentially a lightweight 11-minute capsule of Wagner’s “Tristan” opera whose main revelation is how easily the soprano part in the Liebestod translates to the solo violin (lyrically played by Bing Wang).

Adams closed with a world premiere, “It Got Dark” from Thomas Newman (of Hollywood’s Newman dynasty), a concerto grosso for the Kronos Quartet and orchestra. Of all the music heard on this night, this piece had the closest ties to modern, multi-styled film scoring – eight disconnected, scene-setting, mostly dark-shaded landscapes and meditations, with one bright section flooded with Americana and two intrusive interludes of elderly taped voices.

Designed to evoke memories of Venice beach and the Santa Monica Mountains, “It Got Dark” leaves the listener suspended in a vaguely pensive mood.